1. Field of the Invention
The present invention relates to container sealing machines for applying caps to containers, particularly to a high speed in-line (i.e., straight line) capping machine.
2. State of the Art
Straight line sealing machines for sealing containers have been in use for many years. These machines are generally characterized by having a horizontal moving conveyor which carries filled and unsealed containers successively past a cap feeding device, a cap applicator device, and a cap sealing device. Although the known machines have proven capable of providing satisfactory operations, these prior machines have consistently shown an inability to prevent cocked caps and/or loose caps without scuffing of the cap outer surfaces.
U.S. Pat. No. 3,905,177 (Herzog) issued Sep. 16, 1975 discloses a bottle capping machine in which caps from a hopper are received by each bottle as the bottle passes by, the bottles are then moved between two belts that move at the same rate of speed as the conveyor belt. The two belts prevent the bottle from rotating as it passes between two rows of oppositely rotating wheels that turn the caps down on the bottle. The bottle grasping belts disclosed in Herzog are not synchronized with the rotating wheels.
U.S. Pat. No. 4,559,760 (Daniels et al.) issued Dec. 24, 1985 and U.S. Pat. No. 4,279,115 (Roberts et al.) issued Jul. 21, 1981 disclose capping machines that are provided with height and width adjustments. Both height and width adjustments can be made for containers and closures of different sizes. These capping machines use an endless belt that contacts the top of the closure (i.e., lid) in an off-center fashion to rotate the lid onto the container.